One vertex per element, one color per generator, with an edge from x to x·s.
(2,4)(6,7)(8,12)(13,14,18,16)(15,17,20,19)(21,22,25,27)(23,24,28,26)(5,6,9,7)(8,10,12,11)(13,15,18,20)(14,19,16,17)(21,23,25,28)(22,26,27,24)(8,12)(10,11)(13,14,18,16)(15,17,20,19)(21,24,25,26)(22,23,27,28)(1,2)(3,4)(5,7,9,6)(8,11,12,10)(13,16,18,14)(15,17,20,19)(21,22)(23,24)(25,27)(26,28)(5,8)(6,10)(7,11)(9,12)(13,17)(14,15)(16,20)(18,19)(21,24)(22,23)(25,26)(27,28) involution — undirectedA Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.